1. Field of the Invention
The present invention relates to a controller for power conversion, especially to a controller using a single pin to provide a protection function and a frequency-reduction function for a power conversion application.
2. Description of the Related Art
As energy efficiency and safety of a power converter are more and more demanded globally, the controller thereof is required to provide more and more power-saving and power-protection functions. However, due to limited number of pins, most small-form-factor controllers are hindered from implementing such functions.
One solution is to use a package of larger pin count. However, this will increase the manufacturing cost—as both the package size and the board area will increase. Besides, a controller with a larger pin count can be incompatible with the existing architectures of the power converters.
To solve the foregoing problem, a novel controller is needed.